To assess students' prior knowledge, provide each student with a set of at least three shapes of varying size--small, medium-small, medium, medium-large, or large.
Ask the students to arrange the shapes from left to right, from smallest to largest. It is best not to model before you determine what the students know.
Provide the students with a blank piece of paper and ask them to draw or trace the shapes from smallest to largest.
Reviewing the students' work samples will help you know where to begin your instruction.
Keep the work samples for the duration of the unit so that you can measure the students' growth in understanding of the concepts of the lesson.
To begin the lesson, model different ways to sort objects. For example, you might place the names of the days of the week on paper strips and ask the students to determine a sorting rule for them. The days of the week for the paper strips are provided for you in the Days of the Week sorting cards.
Students might suggest categories such as school days and weekend days. They might also suggest sorting by beginning letters.
Divide the class into small working groups. Include students with varying levels of knowledge and experience in each group.
Give the students a collection of objects, such as pattern blocks, small toys, models of fruits and vegetables, plastic animals, building blocks, buttons, bread clips, bolts, and keys. Have them discuss possible ways to sort, and choose a rule for sorting.
Ask the students to label the sets with an appropriate rule--size, color, shape, objects that will roll or will not roll.
Reconvene the whole class and discuss properties that the students used for sorting. List these on a chart and post the chart in the classroom for future reference.
Have the students return to their small groups and take turns sorting objects in ways that were different from previous sorts. Suggest that they use the properties identified by the group or new properties that emerge from their growing understanding.
One way to decide who should go first is to have the student whose birthday is nearest to the current date lead and then have the student with the next closest birthday go next. This turn-taking models yet another sorting scheme.
After each turn, ask the students to draw a picture showing one of their sorts or to write a statement about it. For younger students, it might be helpful to use recording tools such as stamps of pattern block shapes, stickers featuring the pictures of animals, cut-out shapes, or other pictorial representations of objects used for sorting.
Allow enough time for the students to make several sorts and record at least one. Have the students share their recordings with the class. If the students used properties that were not included on the class chart, add those properties to the list. Save the recordings to use for review during the next lesson.
